1. Technical Field
The present application is directed to an illuminated viewing assembly, a viewing system including the illuminated viewing assembly, methods of use for both and, in particular, to an illuminated viewing assembly and method of use that provides images that may be viewed from any position orthogonal to, and from a plurality of positions oblique to the viewing assembly.
2. Related Art
There are many instances in which it is desirable to provide a picture or display simultaneously and continuously to a group of people. Examples of such instances include business meetings, at airports and other transportation centers, shopping centers, and anywhere large numbers of people are assembled or congregate. Such displays are difficult to provide when several people wish to view the display simultaneously from a variety of locations, because conventional display systems generally cannot be viewed from the rear or extreme sides. Conventional displays are limited to situations in which a viewer""s line of sight is precisely normal to the plane of the picture. Thus, the area from which a viewing audience may be accommodated is limited to locations with suitable sight lines. As a result, use of available space near and around conventional display systems is often limited.
Some attempts to solve this problem have involved displays rotating through 360 degrees. Such displays have permitted several people surrounding the display to view the display. The rotation of such displays must be relatively slow in order to permit the various viewers to have an opportunity to study the display. Such a slow rotation means that essentially only a few people at a time may view the display, while others out of the line of sight must wait until the display comes into their line of sight.
U.S. Pat. No. 3,863,246 to Treka et al. discloses a back lighted display apparatus.
U.S. Pat. No. 3,976,837 to Lang discloses an apparatus for projecting an image onto a rear view screen positioned in a vertical plane which can be rotated extremely rapidly about a vertical axis exactly bisecting the picture in the plane.
U.S. Pat. No. 4,943,851 to Lang et al. discloses a viewing system that includes a liquid crystal display screen including a plurality of LCD panels positioned in a stationary position around a rear projection screen.
U.S. Pat. No. 4,979,026 to Lang et al. discloses a viewing system in which an image is projected from a CRT.
U.S. Pat. No. 5,152,089 to Bellico discloses a multi-image sign display.
Recently, billboards have been displayed that appear to include louvers that allow viewers passing by the billboard to view two different images, depending on the angle at which they pass by the billboard.
There remains a need for improved systems for providing displays that will permit persons located at any position around the display to examine the display substantially simultaneously.
Historically, cinema-photographic projections are based on projecting a sequence of images in the form of a linear strip of translucent film onto a reflecting screen at a rate that allows the effect of persistence of vision to occur. Persistence of vision is a physiological term that describes how the human brain retains an image cast upon the retina for an instant after the object viewed is removed or changed. The entire concept of cinema is based on the effect of persistence of vision. In cinema, the rapid sequencing of images is provided by a mechanical shutter that closes, advances, aligns, and then reopens to project the film image upon a screen consecutively at a rate higher than the reaction frequency of the human eye.
The present invention utilizes the same principals that form the bases for conventional cinema but in a different arrangement. Images are emitted or reflected from a rotating illuminated viewing assembly, which includes an arrangement of at least one illumination source, at least one image member, and at least one blocking member.
The effect of the blocking member is similar to louvers or venetian blinds whereby narrow strips of light blocking material allow a limited field of view. This field of view can be regulated by the width of the louvers, the distance between the louvers and number of louvers utilized.
As the viewing assembly rotates, the blocking member prevents the viewer from viewing the illuminated image member until the plane of the viewing assembly has rotated to 0 degrees (+ or xe2x88x9224 degrees) of the viewers line of sight. The resulting optical effect is such that as the viewing assembly rotates, the images on both sides of the viewing assembly are presented consecutively without the motion blur that would otherwise be inherent in, for example, a rotating screen. This optical effect is due to the combined effect of the alignment of images on either side of the viewing assembly together with effect of persistence of vision. The optical effect is also affected by the relative thickness of the viewing assembly, i.e., the optical effect is improved as the thickness of the viewing assembly decreases. When viewed at eye level, the perception of rotational movement of the viewing assembly decreases as the distance from the surface of the image member to the axis of rotation is reduced. For example, when viewing the rotating viewing assembly at low speed without the louvers attached, the viewing assembly would appear to repeatedly xe2x80x9cgrowxe2x80x9d from a vertical line until it reaches its full size and then xe2x80x9ccontractxe2x80x9d upon itself. The louvers simply present the illuminated image to the viewer only when it has reached its full size.
Another aspect of the invention is directed to animated imaging, which describes a looped or continuous animation sequence. Animated imaging may be provided by including two images that, when aligned properly in a viewing assembly, are able to create the illusion of perceived motion as the image assembly rotates. One example is the image of a butterfly hovering in mid air as its wings appear in motion, flapping up and down repeatedly. Animated imaging may be provided at predetermined rotation rates at which printed text, graphics, or any combination thereof, may be displayed.
At relatively higher rotational rates, the ability to provide animated imaging is lost. However, at relatively higher rotational rates, the invention may provide flicker-free imaging, which describes the elimination of the stroboscopic effect that otherwise occurs at lower rotational rates. Because the stroboscopic effects are made imperceptible at the higher rotational rates, flicker-free imaging may be used to display printed text, graphics, photographs, or any combination thereof.
It should be noted that the rotation rates of the animated imaging and flicker-free imaging do not necessarily need to remain a constant, and that it may be desirable to change the rotation rate, for example, as part of a presentation, especially if multiple illuminated panels and text are mounted to a single viewing assembly.
Another aspect of the invention is directed to viewing assemblies that include computer and/or video displays. Such displays require rotation rates that are coordinated, and preferably identical to the scan rate of the screens mounted to the assembly. For example, traditional LCD video screens scan at a rate of about 29.97 scans per second. Therefore the screen must rotate at about 29.97 revolutions per second. Scan rates sometimes vary between manufacturers, some manufactures offer screens with adjustable scan rates, and some screens have a xe2x80x9csofterxe2x80x9d scan than do others. Therefore, a precisely regulated rotational rate is not always critical.
When a viewing assembly is rotating continuously it may be necessary or desirable to shield the viewing assembly from unwanted obstacles such as hands or other means of obstruction and to minimize wind resistance to the surface of the rotating viewing assembly. This may be achieved by enclosing the viewing assembly within a housing constructed from a transparent material such as glass or acrylic. The housing may be mounted coaxially with the axis of rotation of the image assembly, which allows the viewing assembly to rotate freely. At high rotation rates, it may be desirable to create an air vacuum within the cylindrical chamber to eliminate wind resistance.
To improve the contrast and overall visibility of the viewing assembly, it may be necessary or desirable to provide a dark background that blocks the view of structures and lights on the opposite side of the viewing system. This may be accomplished by positioning a layer of polarizing film completely around the viewing system such that the angle of polarization is at 45 degrees to horizontal. In this manner, the polarization angle on any two opposing points on the film will be perpendicular and as a result, will block unwanted light. When a polarizing film is disposed on the interior or exterior of the transparent housing, the effect is that of a constant black background behind the rotating viewing assembly.
By means of a rotating viewing assembly of the type described above that is contained within a transparent housing lined with polarizing material, the invention has the unique ability to present animated imaging, flicker-free imaging, and video or computer generated images. When positioned in the center of a room, this imagery is visible to any number of viewers simultaneously within a 360-degree parameter of the display.